Anybody else's mustang idle abnormally high at startup while the car is on a tune?

 

Not mine.....

 

Clean your throttle body, and MAF sensor. 9 times out of 10, a bad/rough idle after tuning is due to a dirty TB, AM/brenspeed all recommend doing it before tuning. If you've already done that (or the problem persists afterwards too), then request a new tune, odds are you just got unlucky with a bad tune- it happens (rarely, but still).

I noticed you're from Indy, anywhere near Indianapolis/Carmel by any chance? You should get on the region chapter- Indiana doesn't seem to have a very active one lol.

 

Who's tune are you running? If it's a Steeda tune, let me know so that I can look into this further for you.

 

How long does your car idle high, once you start it up?
When I start my car, it always idles high for several seconds, then goes down to normal 750 RPM range.

 

It idles for a bout a minute/ minute and a half at about 1500-1600 rpm then goes down to normal

 

I'm running sct tunes from American muscle, thanks anyways!

 

I actually have already ordered new tues and cleaned the tb an no luck. But I have ever touched the MAF, what's it take to clean?

 

Hmm, well I would wait on the new tunes before going any further but there's a chance the MAF could be the problem here (but usually it throws a warning code if that's the issue). You can find some can of MAF sensor cleaner at autozone, or maybe napa usually. I've never done it myself so I would suggest checking some youtube vids to see how they clean them- I think brenspeed might have a cleaning video on it (or maybe that's just for the TB?). Either way, I'm sure other members can chime in on cleaning the MAF sensor better than I can.

But if it's cold out, high idle is a very normal thing as others have said. Mine idles at about 1200-1300 rpm for about a minute (steadily decreasing) until it reaches the normal 650-750 rpm when it's around 30-40 degrees Fahrenheit.

 

Very simple. Take out the two screws, pull the MAF sensor out and and spray down with MAF sensor cleaner. Let it dry for a few minutes, put it back in and put the two screws back in. I picked up a can of MAF sensor cleaner at either Autozone or Advanced Autos, can't remember which one.